Tungsten is a rare metal that occurs naturally on Earth almost exclusively in chemical compounds. Tungsten is an inherently brittle and hard material, which makes it difficult to work.
Protons and Neutrons in Tungsten
Tungsten is a chemical element with atomic number 74 which means there are 74 protons in its nucleus. Total number of protons in the nucleus is called the atomic number of the atom and is given the symbol Z. The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to 1,602 x 10-19 coulombs.
The total number of neutrons in the nucleus of an atom is called the neutron number of the atom and is given the symbol N. Neutron number plus atomic number equals atomic mass number: N+Z=A. The difference between the neutron number and the atomic number is known as the neutron excess: D = N – Z = A – 2Z.
For stable elements, there is usually a variety of stable isotopes. Isotopes are nuclides that have the same atomic number and are therefore the same element, but differ in the number of neutrons. Mass numbers of typical isotopes of Tungsten are 182-184, 186.
Main Isotopes of Tungsten
Tungsten occurs in 5 natural isotopes: 180W, 182W, 183W, 184W and 186W. 180W is very slightly radioactive, decaying by alpha decay with a half-life of 1.8×1018 years. 184W is the most common isotope, having a natural abundance of approximately 30%.
Tungsten-180 is composed of 74 protons, 106 neutrons, and 74 electrons.
Tungsten-182 is composed of 74 protons, 108 neutrons, and 74 electrons.
Tungsten-183 is composed of 74 protons, 109 neutrons, and 74 electrons.
Tungsten-184 is composed of 74 protons, 110 neutrons, and 74 electrons.
Tungsten-186 is composed of 74 protons, 112 neutrons, and 74 electrons.
Electrons and Electron Configuration
The number of electrons in an electrically-neutral atom is the same as the number of protons in the nucleus. Therefore, the number of electrons in neutral atom of Tungsten is 74. Each electron is influenced by the electric fields produced by the positive nuclear charge and the other (Z – 1) negative electrons in the atom.
Since the number of electrons and their arrangement are responsible for the chemical behavior of atoms, the atomic number identifies the various chemical elements. The configuration of these electrons follows from the principles of quantum mechanics. The number of electrons in each element’s electron shells, particularly the outermost valence shell, is the primary factor in determining its chemical bonding behavior. In the periodic table, the elements are listed in order of increasing atomic number Z.
Electron configuration of Tungsten is [Xe] 4f14 5d4 6s2.
Possible oxidation states are +6.
Most Common Compound of Tungsten
Tungsten carbides (W2C and WC) are produced by heating powdered tungsten with carbon. Approximately half of the tungsten is consumed for the production of hard materials – namely tungsten carbide – with the remaining major use being in alloys and steels. Mining and mineral processing demand wear-resistant machines and components, because the energies and masses of interacting bodies are significant. For this purposes, materials with the highest wear-resistance must be used. For example, tungsten carbide is used extensively in mining in top hammer rock drill bits, downhole hammers, roller-cutters, long wall plough chisels, long wall shearer picks, raiseboring reamers, and tunnel boring machines.
|Number of protons
|Number of neutrons (typical isotopes)
|Number of electrons
|[Xe] 4f14 5d4 6s2